When Spencer Tracy signed with MGM, he was a character actor better known for his problem drinking (and very public extramarital affair with Loretta Young) than for his movie hits. But the studio made him a star, and by the time Katharine Hepburn was looking for a male star who could play a prototypical American male opposite her very idiosyncratic persona, Tracy was the obvious choice. Tracy and Hepburn became one of the most legendary Hollywood couples of the century, on-screen and off, and their partnership helped to canonize both as important stars. But their personal relationship was complicated by his drinking and his relationships with other women -- including his wife.

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The "most recent biographies" of Tracy and Hepburn mentioned in this episode are William J. Mann's Kate: The Woman Who Was Hepburn and James Curtis' Spencer Tracy: A Biography. The latter disputes the former, at least where the sex lives of its subjects are concerned. I'm honestly not sure what to believe about Tracy and particularly Hepburn's sex life, and I'm honestly not sure it really matters; what's more interesting to me is the ways in which stories/rumors/ideas about famous people circulate in the culture and become a part of their history, whether they're true or not.